Motor vehicle theft is an ever-growing problem today and one which results not only in considerable cost and dismay to a stolen vehicle's owner but, in the long term, one which results in higher costs to all holders of vehicle insurance policies and, indeed, to all policy holders in general.
Various devices and systems using discomfort-causing substances have been proposed, one such being disclosed, for example, in the specification relating to PCT Application No. PCT/FR85/00244 of Sept. 10, 1985. In this document, a device using an existing windscreen washer element or elements of a motor vehicle to generate sprays of showers of "chemical liquids such as ammonia, sulphuric acid, and hydrochloric acid, and dyes ----" is installed in a vehicle, apparently with the aim of "-- marking, hurting, asphyxiating --" a would-be thief.